Could Forage Palm and Stone Barrier Be as Effective as Native Vegetation in Controlling Runoff and Erosion in the Brazilian Semiarid Region?

Abstract

Most lands in the Brazilian semi-arid region are covered with native vegetation (Caatinga) with limited agricultural practices due to chronic water-scarcity issues. However, clearing the native vegetation and using the land for agriculture is becoming a common practice. The objective of this study was to evaluate the effectiveness of forage palm and stone barrier in reducing runoff and erosion compared to native vegetation. The study was conducted in the Jatobá experimental basin, Brazil, using runoff plots with three surface covers: Caatinga, forage palm barrier, and stone barrier. Data collection includes runoff and erosion rates, and soil moisture dynamics at two depths (0–20 and 20–40 cm) in response to rainfall events. Rainfall characteristics were also recorded and analyzed for 30 min for intensity (I30) and erosivity (EI30). Results showed that stone barrier and forage palm treatments were not as effective as the native vegetation Caatinga in reducing soil loss. Stone barrier was the least effective in reducing runoff and soil loss. However, runoff from forage palm was not statistically different from Caatinga. In addition, forage palm improves soil moisture dynamics at two depths. The study findings highlighted the importance of the Caatinga for soil, water and biome conservation in the region. However, the study also suggested that in the places where agricultural practices are conducted, using forage palm as a soil-conservation strategy could be a good alternative. Additional benefits of forage palm include its suitability for intercropping with other crops, and that it can serve as an alternative for animal feed in the region. Information from this study could be used to inform land management and soil- and water-conservation efforts in the semi-arid region of Brazil.

Keywords

• soil moisture
• soil and water conservation
• sediment
• rainfall